<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
	<script type="text/javascript">
		function lei() {
			alert("欢迎学习javascript");
		}
	</script>
</body>
<input type="button" value="单机" onclick="lei()"></input>
</html>